Economist Thomas Sowell points out that the housing bubble in the United States was primarily restricted to certain areas like coastal California with extensive land use regulations, restricting the amount of land available for building. Reduced supply raises prices. High prices created a demand for risky mortgages to pay for them.
In late 2005, the booming U.S. housing market seemed to be slowing. The Federal Reserve had begun raising interest rates. Subprime mortgage company shares were falling. Investors began to balk at buying complex mortgage securities. The housing bubble, which had propelled a historic growth in home prices, seemed poised to deflate. And if it had, the great financial crisis of 2008, which produced the Great Recession of 2008-09, might have come sooner and been less severe.
At just that moment, a few savvy financial engineers at a suburban Chicago hedge fund helped revive the Wall Street money machine, spawning billions of dollars of securities ultimately backed by home mortgages.